Apparatus for sweating or treating paraffin wax or the like



Feb; 1933. A. D. ARMSTRONG ET AL APPARATUS FOR SWEATING OR TREATINGPARAFFIN WAX OR THE LIKE 3 Sheets-Sheet l u 1 Q fizz e/226225 239 m WagFeb. 21, 1933.

A. D. ARMSTRONG ET AL APFARATUS FOR SWEATING OR TREATING PARAFFIN WAX ORTHE LIKE Filed July 6, 1928 3 Sheets-Sheet 2 1933. A. D. ARMSTRONG ET AL8,930

APPARATUS 'FOR SWEATINYG OR TREATING PARAFFIN WAX OR THE LIKE Filed July6, 1928 5 Sheets-Sheet 5 Patented Feb. 21, 1933 ALBERT DOUGLAS ARMSTRONGAND GAVIN CHAPMAN GORDON BOBBIE, OF RANGOON,

INDIA, ASSIGNORS TO THE INDO-BU'RMA PETROLEUM COMPANY LIMITED, F

RANGOON, BURMA APPARATUS FOR SWEATING OR TREATING PARAFIEIN WAX OR THELIKE Application filed July 6, 1928, Serial No.- 290,785, and in GreatBritain July 8, 1927.

This invention relates to the manufacture of parafiin wax and has forits ObJGCt to provide an improved apparatus for sweating the wax inacake of such thickness that a wax of a high degree of purity is obtainedin one operation.

'Hitherto it has been customary to sweat paraflin scale in cakes seldomexceeding SIX inches in thickness, with the result that the sweated cakeof wax always contained a small percentage of oil to remove which it wasnecessary to resweat the cake. By the apparatus formerly employed oilcould not be properly drained from a greater thickness T than six inchesof scale if the latter was comparatively rich in wax.

By the present invention the body of the wax mixture is prevented, bymeans of multiple layers of small bore piping arranged in a series ofclosely spaced vertical coils, from forming a compact mass,'the pipes sobreaking up and supporting the cake as to permit of rapid drainage ofoil from the A mass, thus making it possible to treat a body of wax of amuch greater thickness than six inches.

The piping must lie horizontally in the mass otherwise a proper supportof the cake does not occur. Vertical pipes do notrealize the resultaimed at.

A body of scale of greater thickness than six inches requires a longperiod in which to cool, for which reason mass breaking agents as anyconvenient cooling medium may be pumped through the pipes to bring aboutrapid crystallization of the wax.

The vat or container has a suitably sloped bottom for draining purposes,a perforated false bottom or wire cloth horizontal screen is supportedabove said bottom, and a space for the wax to be treated is providedabove said bottom or screen. By reason of a support such as thatreferredto above a greater depth ofwax may be treated than could betreated in the absence of said support. v

In this apparatus the horizontal elements may be in the shape of amultiplicity of tubes,

preferably forming continuous coils, which may be caused to cool or toheat the wax by circulating fluid therethrough at desired temperatures.

The apparatus may comprise atank or vat having a bottom inclined to oneor more draining points provided with cocks, or valves, a horizontalshelf ofwire cloth suitably supported above said bottom, multiple layersof horizontal piping placed above the wire cloth and braced or supportedso as to be capable of assisting in sustaining the whole or part of theweight of the wax, means whereby fluid, either cooled or heated, may becirculated through said piping, and a steam pipe through whichsteam maybe passed into the tank when desired.

The whole apparatus may be assembled in a room or chamber, for clallyconstructed chamber, into which the co ls'or pipes may be introducedthrough a suitable end door. The room or chamber will be adapted to besuitably heated or cooled when necessary to assist the process.

One form of apparatus suitable for the practlce of this invention isshown, merely by way of illustration, in the accompanying drawings whereI Figure l is a side elevation of the sweating pan;

Figure 2 is a sectional elevation showing the p'pe coils with inlet andoutlet header pipes in position; I

Figure 3 is a planof the sweating pan with a convenient number of pipecoils at suitable pitches;

Figure 4L is a plan showing the header pipe with branches to which thepipe coils are connected;

Figure 5 is a part sectional elevation showing the relative and meltingpipe;

Figure 6 is a plan of the frames to which are attached the expandedmetal and wire cloth;

Figure 7 is an end sectional elevation of the sweating pan; Figure 8shows one shaped side plate;

Figure 9 shows the other shapedside plate, 1

example into a spe' the room showing the tank or vat and room heatingcoils in position;

Figure 11 is a sectional end elevation of the room showin the tank orvat and the room heating coi s in position;

Figure 12 is a sectional plan showing arrangement of room heating coil.

Referring to the illustrations the construction of the apparatus is thusdescribed.

A steel pan or tank 1 (Figure 1) is supported in an elevated position;for this purpose Vertical posts 2 and horizontalbeams 3 of channel orother suitable section may be used as the supporting structure.

The side lates 4 and 5 of the pan may be she "as shown inFigures 8 and 9andbe of unequal depth; the bottom plates 6 are conveniently welded orotherwise fixed to theahaped ed e of the side plates, thus affordingsuitab e inclines to permit of eflicient from the pan. Facility indraining is an important point to consider in the construction of theapparatus. An end plate 7 may bebolted or otherwise secured in position.This arrangement facilitates the assembling of the apparatus and allowsof the whole bein placed in a room or house, 21, of correct vo umewithout having to provide for constructional head room.

Frames of suitable rolled steel sections, such asan le iron 9, fittedwith wire cloth 10 supported expanded metal 11 (see Figure 6) are fittedas shown in Figure 7 over the whole area of the pan.

Pipe coils 12 are placed in the pan, being suspended from beams 13 bysuitable hangers or otherwise supported; the beams 13 rest on the upperedges of the side plates 4 and 5. Connecting al coils 12 is one inletpipe header 14: deliver to the lower ends of the coils and one out atpipe header 15 taking of! the heating or cooling fluid from the upperends of the coils; the coils 12 and headers 14: and 15 should preferablybe made of copper, but ordinary steel or other tubing will serve.

Melting out pipes 16, with controlv valves 17, are placed in thedraining channels (see Fi res 1, .2 and 7). Draining or run oil cooqi sor valves 18 with suitable tail pipes 19 are fixed at the low ends ofthe draining chan- 11618. A suitably sized gutter 20 is placed toconduct the sweated cuts to" the receiver The mode of operation of theapparatus is as follows :Water is run into the .tanktill it reaches thelevel of the wire cloth 10. The wax mixture is then run in till the tankis full. Water or other cooling medium at a suitable temperature issimultaneously or subsequently passed through the pipes 12, till themass of the wax mixture has cooled to a suitable temperature and hasmore or less solidified or or stallized. Cock'or valve 18 is then openthus permitting the water charged inthe first operation to run ofi andsweating to commence. As drainage of the oildiminishes in volume thetemperature of the room 21 is gradually raised to the required degree bymeans of the heating coils 22. This operation of raising the cake of waxmixture to the required temperature may be assisted b passing water orother medium at a suitab e temperature through the coils 12, and as thetemperature of this water is slightly higher at the lower or inlet endsof the coils than at their upper or outlet ends,

a temperature gradient is established which facilitates the sweatingoperation, and moreover-a substantially uniform temperature ismaintained on any given horizontal plane of thewaxmass. Y

When'the wax cake has reached the desired degree of purity it is meltedout by opening steam valve 17 and passing steam into the tank throughpipes 16. .7 V

Theimproved apparatus permits a cake of any desired thickness to berapidly and efiiciently sweated. i

The apparatus yields a quality of wax superior to and of higherpercentage of white paraflin wax than that yielded by any other knownsweating apparatus. a

The improved apparatus is particularly adapted to-the ra id. cooling andsweating of large volumes 0 wax mixture with a minimum amount of labor.

By the utilization of the apparatus herein described the chilling andthe heating and breaking up of the cake of wax may be performed in amuch more efiicient manner than has usually been done.

A much greater thickness and volume of wax may be treated at one timeand the drains ing end sweating with this greater depth is found to bebetter so that a is practically free from 0i may be. produced in asingle treatment. The parafiin wax indeed maybe treated according tothis process to' porduce a practically tasteless, odorless wax of stablecolour in a single operation. The percentage of yield of white paraffinwax by this process is very high. The plant may, moreover, be workedwith the minimum amount of labor for handling'li'ke volumes, and theminimum expenditure in fuel. The apparatus in fact produces in a giventime a much greater amount of white wax than has been produced by anyother apparatus known to the applicants.

It will of course be understood that the invention is not limited in itsapplication to the apparatus illustrated, but that considerablemodification of the same and of its details and lay-out may be carriedout'without departing from the scope of the invention.

Apparatus. for the heat treatment of wax is known comprising a closedvesel'or wax container sealed by fillingthe vessel or conminer with waxor wax mixture to the excln sion of air and having means for efiectingaraifin wax which uniform heating or cooling of the Wax throughout thevessel or container. In such apparatus it is known to have a closedouter shell and a plurality of superposed and 5 spaced substantiallyhorizontal heating cells therein, these cells being of a flat shape,hollow inside, so as to divide the vessel into compartments into whichthe Wax is filled. The said compartments are relatively small and areprovided with gauze bottoms and with vertical gauze partitions or sidesto engage the wax. The wax whilst being treated is supported by thegauze bottoms, these in turn being placed on iron rods, which again aresupported on cross bars. The wax in the various small compartments aresupported practically wholly by the gauze. Hot or cold liquid may becirculated through the cells.

Now according to the present invention the interior of the apparatus isnot divided up into a multiplicity of small compartments with thenecessary attendant complications in construction and up-keep, in whichcompartments the wax is supported mainly by the gauze bottoms, but is,on the other hand, treated in a much simpler and robust plant in whichthe wax is in a large vessel and is more or less completely supportedand broken up by a multiplicity of horizontal elements, which, beingclosely spaced, entangle and break up the wax and by the frictionalresistance to movement therebetween owing to their passing through andbeing embedded in the body of the wax they hold the wax, relieving thepressure on the gauze bottom below. A greater depth of wax can thus bedealt with in a single vessel or compartment.

It will be noted also that the said supporting or entangling elementsare, according to the present invention, in the shape of tubes, whichare robust members and not likely to be damaged or to get out of order,whereas in the known apparatus referred to above the wax is supportedmainly by wire gauze which largely fills the vessel making repairs orinspection very difficult.

It will further be observed that the said entangling and supportingelements being tubes, the heating or cooling fluid may be passedtherethrough in intimate contact with the whole body of the wax whereasin the known apparatus referred to the cells are, relatively speaking,large and only the ex terior of each compartment into which the vesselis divided by said cells is heated or cooled.

Having now particularly described and ascertained the nature of our saidinvention and in what manner the same is to be performed, we declarethat what we claim is 1. An apparatus for sweating or purifying paraffinwax mixture, scale or the like, comprising a sweating pan or Vat, ahorizontal foraminous shelf in said pan or vat, a

multiplicity of layers or horizontal pipes constituted by a series ofvertical coils each consisting of a serpentinous pipe within the panabove said shelf, said layers of horizontal pipes serving to support acake of wax or the like and to prevent it from forming a compact mass,means for introducing heating and cooling fluids into the said pipes,means for introducing wax mixture or the like into the pan, and meansfor withdrawing oil from said pan.

2. An apparatus for sweating or purifying paraflin wax mixture, scale orthe like, comprising a sweating pan or vat having a bottom inclined to aplurality of draining points, drain cocks connected to said drainingpoints, a horizontal f'oraminous shelf supported above said bottom,multiple layers of horizontal piping situated above the said shelf andconstituted by a series of vertical coils each consisting of aserpentinous pipe, said coils serving to support thecake of wax and toprevent it from forming a compact mass, means for admitting heating andcooling fluids to said piping for circulation therethrough, means forintroducing wax mixture or the like into the pan, and means foradmitting steam to said pan.

3. An apparatus according t9 claim 1 wherein the coils are spaced moreclosely horizontally than the vertical spacing of the convolutions ofeach coil.

In testimony whereof we hereto aflix our signatures this fourth day ofJune 1928.

ALBERT DOUGLAS ARMSTRONG.

GAVIN CHAPMAN GORDON BOBBIE.

